NIST logo

Publication Citation: Multiple-order Imaging for Optical Critical Dimension Metrology using Microscope Characterization

NIST Authors in Bold

Author(s): Jing Qin; Hui H. Zhou; Bryan M. Barnes; Francois R. Goasmat; Ronald G. Dixson; Richard M. Silver;
Title: Multiple-order Imaging for Optical Critical Dimension Metrology using Microscope Characterization
Published: October 11, 2012
Abstract: There has been much recent work in developing advanced optical metrology applications that use imaging optics for optical critical dimension (OCD) measurements, defect detection, and for potential use with in-die metrology applications. We have previously reported quantitative measurements for sub-50 nm CD dense arrays which scatter only the 0th-order specular diffraction component using angle-resolved scatterfield microscopy. Through angle-resolved and focus-resolved imaging, we now access the three-dimensional scattered fields from OCD targets that contain multiple Fourier frequencies. Experimental sensitivity to nanometer scale linewidth changes is presented, supported by simulation studies. A new, more advanced approach to tool normalization is coupled with rigorous electromagnetic simulations and library based regression fitting that potentially enables OCD measurements with sub-nanometer uncertainties for targets that scatter multiple Fourier frequencies.
Conference: SPIE Optics & Photonics 2012
Proceedings: Instrumentation, Metrology, and Standards for Nanomanufacturing IV, Proceedings of SPIE Volume: 7767
Volume: 8466
Pages: 12 pp.
Location: San Diego, CA
Dates: August 12-17, 2012
Keywords: optical metrology; electromagnetic simulation; frequency domain tool normalization; multiple frequency scattering; evaluate sensitivities and uncertainties; phase sensitive measurements;
Research Areas: Critical Dimension and Overlay Metrology, Optical Metrology
DOI: http://dx.doi.org/10.1117/12.946120  (Note: May link to a non-U.S. Government webpage)